With the progress of communication systems, a wide variety of wireless terminals have been introduced to consumers such as companies and individuals. A current mobile communication system affiliated with Third Generation Partnership Project (3GPP), for example, Long Term Evolution (LTE), LTE-Advanced (LTE-A), and the like, is a high-speed and high-capacity communication system capable of transmitting and receiving various data, such as image data, wireless data, and the like, beyond providing voice-oriented services. Accordingly, the current mobile communication system needs to develop a technology capable of transmitting a large amount of data coming close to the amount of data transmitted through a wired communication network. As a scheme for transmitting a large amount of data, there is a scheme for efficiently transmitting data by multiple cells. However, when data is transmitted by multiple cells or multiple transmission/reception points, collision between signals may occur, and thus problems may arise.